The research is intended to develop a prototype of an automated commercial ultrasound mammography system with a spatial resolution similar to x-ray mammography systems and based on combined tissue and blood flow imaging. The blood flow imaging is significant, since malignant tumors exhibit dramatic, locally increased vascularity and blood flow. The Doppler color flow mapping instrument is intended initially as an adjunct to X-ray mammography, but may also be used as a screening device. To overcome the limitations of conventional ultrasound mammography, the proposed work will include new imaging concepts. In the existing laboratory model completed under the Phase I grant, the received pulse-echo ultrasound RF data of a full image is digitized which gives greatly incresed flexibility of software processing. The digital signal processing produces both a tissue structure image and a blood flow image of the scanning plane. For evaluation of the mammography system, ultrasound scanning of normal volunteers at different times through the menstrual cycle, and of women with diagnosed breast cancer is planned. Images will be generated using different standard and proprietary algorithms off line, for comparison with surgical and histological findings to determine optimal processing methods. This work will begin in the first year. In the second year a marketable prototype will be developed for real-time clinical use. This approach will allow all patient data to be processed with the same algorithms so that most up-to-date processing can be used on the entire data set. The clinical instrument prototype will be able to use the technology current at the end of this clinical series, instead of that available at the start, and thus reduce costs and avoid technological obsolescence.